Is that not exactly what the original English title implied, albeit rather more poetically?

It does annoy me slightly though, when translations take out all the poetry of originals, leaving it at base denotative meaning. I know you have to be wary of idiomatic mis-translations, but Olympus Descending isn't really an English idiom, is it? Maybe German culture just doesn't reference Greek myth as easily as British/American/Canadian culture does, I don't really know.

I don't know but "Abstieg vom Olymp" is being used quite often in German. Though it might have a slightly different connotation because it typically refers to a single person coming down from a high position. "Olympus descending" sounds to me more like the whole olymp is falling apart, which might be what was supposed to be alluded to in the novel.